Field of the Invention
The present invention relates to a pressure reduction-absorbing bottle. Priority is claimed on Japanese Patent Application Nos. 2017-060399 and 2017-060398, filed Mar. 27, 2017, the content of which is incorporated herein by reference.
Description of Related Art
In recent years, as a pressure reduction-absorbing bottle made of a synthetic resin material in a cylindrical shape with a bottom, for example, as shown in Japanese Unexamined Patent Application, First Publication No. 2013-23278, a constitution in which a bottom wall portion of a bottom portion of a bottle includes a grounding portion at an outer circumferential edge, a rising circumferential wall portion connected to the grounding portion from an inner side of the bottle in a bottle radial direction and extending upward, an annular movable wall portion extending from an upper end portion of the rising circumferential wall portion toward an inner side of the bottle in the bottle radial direction, and a central wall portion connected to an inner end portion of the movable wall portion in the bottle radial direction, in which the movable wall portion is rotationally moved upward together with the central wall portion about a connection portion between the movable wall portion and the rising circumferential wall portion so that pressure reduction in the bottle is absorbed has become known. In order to secure a pressure-reduction absorbing capacity after filling of contents, this kind of pressure reduction-absorbing bottle is sealed in a state in which the bottom wall portion is deformed at the time of filling of the contents so that the central wall portion is displaced downward.
However, in the pressure reduction-absorbing bottle in the related art, the movable wall portion is less likely to be rotationally moved evenly upward over the entire circumference when a pressure in the bottle becomes negative after sealing is applied. In this case, the appearance of the pressure reduction-absorbing bottle is likely to deteriorate and a height position of a liquid surface is likely to be different for each of pressure reduction-absorbing bottles despite being filled with the same amount of contents.
Also, if this kind of pressure reduction-absorbing bottle is sealed in a state in which the bottom wall portion is deformed at the time of filling of the contents so that the movable wall portion is greatly displaced downward, a large pressure-reduction absorbing capacity can be secured. As means for increasing such a pressure-reduction absorbing capacity, a constitution in which the rising circumferential wall portion is greatly inclined inward in the bottle radial direction may be adopted and thus it is conceivable that it would be easy to displace downward the whole of the bottom wall portion further inward in the bottle radial direction than the grounding portion at the time of filling of contents.
However, in such a pressure reduction-absorbing bottle, the rising circumferential wall portion is rotationally moved downward about a connection portion between the rising circumferential wall portion and the grounding portion at the time of filling of contents. For this reason, for example, ground-contact stability is likely to deteriorate due to the occurrence of unnecessary deformation of the grounding portion such as large local deformation of part of the grounding portion.
Therefore, an object of the present invention is to provide a pressure reduction-absorbing bottle in which a movable wall portion can be rotationally moved evenly upward over the entire circumference when a pressure in the bottle becomes negative after sealing is applied and a pressure-reduction absorbing capacity can be increased without deteriorating ground-contact stability at the time of filling of contents.